If you ever tried to segment a list by engagement, you may have wondered about our member-activity rating. I’m talking about the little stars that look like restaurant reviews for your subscribers. I’m not sure how five-star restaurants get their rating, but I suspect it’s a little different than email.
To come up with a member rating, MailChimp tracks open and click data and measures that against your sending frequency. Actually, we get a lot of questions about these little stars and how exactly a two star subscriber becomes a five star subscriber. To find out how the sausage is made, we’ll need to look at the code behind member ratings.
Our five star system is based on a twenty point activity score, and we weight those activity scores unevenly. An even distribution might be good for my OCD, but loading activity points around four and five stars ensures that high engagement is easily remembered while low engagement is easily forgotten.



